Automatic Radio Beacons

Radio Record, Volume III, Issue 19, 22 November 1929, Page 31

Automatic Radio Beacons

‘" Along Coasts of Canada HED first of the eighteen radio beacons which the Canadian Government is installing’ along the, Atlantic and Pacific coasts has recently been completed, and after strenuous testing, has been declared entirely satisfactory. These radio beacons, which are entirely automatic, are now being installed to supply a long-felt want, ’ namely, some reliable means whereby shipping is afforded an adequate measure of protection from the dangerous shoals and fogs which prevail on the Northern Canadian coasts. ¢ These radio beacons are to be inStalled in every lighthouse along the coasts, and though their transmissions are entirely automatic, it is necessary for the lighthouse-keeper to ensure the constant running of the gasoline unit which supplies the necessary power. The radio apparatus consists of a duplicate automatic transmitte. which emits a set code signal, thus enabling a radio operator on board ship to ascertain his whereabouts with accuracy. In the case of a breakdown, the keeper merely throws a switch over, and thus places a duplicate transmitter on the air. oy Each of the beacons will have a .special code signal of its own, and when an operator hears one of these signals he can be sure that his ship is near ‘some dangerous location. If his ship carries direction-finding apparatus, he can locate the position of the ship by ascertaining the direction in which the signals are loudest. By taking crossbearings from another beacon station, the exact position of the ship can be accurately plotted. : The beacon transmitters are so designed that about the only breakdown that is possible is one caused by a burnt-out valve. Should this occur, the keeper immediately places the other set in action, and substitutes another valve in the defective transmitter, Adequate warning is given, should anything go wrong, by a bell, which continues ringing until the transmission recommences. ‘ ; The .operation is entirely controlled ~by a clock. As the hands reach the set time, special electric contacts close the circuit and start the gasoline unit. |When the engine is properly running, Mlectric contacts on the power panel of the transmitter close and start up the motor-generator which supplies the current for the transmitter; the valves light up, and within one minute and forty-five seconds from the time that _ the clock closed contact the signals are

on the air. They continue for one minute, just sending out the call, such ‘as VGZ, VGZ, ¥GZ, for a full minute. Then a two-minute pause follows; the signals go on again; another two-min-ute pause. Then the carrier note which goes out on the.air is shut off; as the second contact on the clock closes the circuit. Once an hour, twenty-four times a day, 865 days in the year, that automatic procedure goes on. Only in fog will the transmitter function, continuously, twenty-four hours a day. The beacons operate on @& Waver length of 1000 metres, and are powered with four fifty-watt transmitting valves. They have a positive range of 75 miles, while their signals have been heard loudly enough for direction-find-ing operations up to distances of 200 miles or more. It is expected that this ehain of eighteen stations will be completed early in the coming year, and when completed, it will form yet another addition to the already large number of stations which are operated by the Canadian Government for the aid of marine navigation.